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And did my first try with non-autonomous flight :

;)

Yesterday, Steve Jobs announced the iPhone 4g... and to my ears, he was really announcing not the latest phone from apple, but the "iDrone". As I heard him talk about the new gyro built into the phone... I started adding the feature set... a fast CPU, lots of memory, built in GPS, compass, accelerometer and now a gyro... of course it could pilot a UAV!

With the built in cameras, it could do photo and video recon... and since it has two cameras (provided they can both be made to operate at the same time), add a couple of mirrors and the craft could do 3D images in real time... to assist in terrain mapping or landing.

It sports a good set of software development tools and on the whole, probably weighs less than all of the same components placed together, and at only $200 it's ecoconomical.

This is a project that could really get off the ground!

Hello all, I've been toying around with the MikroKopter Hexakopter as a tool for aerial mapping and photogrammetry. After a few weeks of learning the ins and outs of the system, I finally had some time on the weekend to test the system for mapping.

In short, we placed Ground Control Points (GCPs) around a man-made ponding area at roughly ten meter intervals (~40 x 30 m in total area). The GCPs were shot in with a deferentially-corrected GPS (~0.1 m horizontal and ~0.2m vertical resolution) and with a Total Data Station (>0.03m vertical and horizontal resolution). We then flew the Hexakopter at 40m above the ground surface in an east-west grid pattern with a photograph being taken straight down every 10 m or so. The camera used was an off the self Canon A540.

The photographs were processed to remove most distortion and dropped into a photogrammetry program. A 0.05 m resolution DEM and 0.02 m photomosaic was created from 22 images. It took about two hours to collect the photographs, and shoot in the GCPs with both the DGPS and TDS. Processing of the imagery was nearly flawless and took about two hours as well. This time can probably be reduced to an hour or less.

Compared to doing this same process with a kite or blimp, I am very impressed with the Mikrokopter (and multi-copters in general) as a platform for high resolution, low altitude mapping. Let me know what you think.

Over the next few weeks, I'll be testing the same process in at a couple of archaeological sites in the southwestern US. I'll share some of those results when they are complete.

Can't wait to play with the truly opensource Ardupilot!

-Mark

Photo credit: Wired January 2006 article on Stanley, Stanford's entry into the 2005 DARPA Grand Challenge: http://www.wired.com/wired/archive/14.01/stanley.html

There are all kinds of ways in which a distributed flight array could be useful. One of the most obvious is heavy lifting… Got something heavy? Call in a bunch of robots to combine and lift it. Got something heavier? Call in a bunch more. If one robot breaks, it’s not a big deal, since you can just swap in another one. The robots are even able to adapt on the fly to keep the entire array stable, so adding and removing individual robots is relatively straightforward. Still, getting the robots to reliably dock with each other in mid air is probably easier said than done… We’ll definite be looking forward to seeing some video of that in action."

[ DFA ]

I have been asked if I would mind supplying the SET file for my Stryker. See attached. Please keep in mind if you plan on using this with a differnet AP other then Atto then P and D gains may be way far off. Our scaling factors may not meet eye to eye. I also have added rudders for active yaw dampening.

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$1,Mix Enable = 1 ' 0 or 1 allowed. Enable flag for Elevon/V-tail mixing. 0 = FALSE, 1 = TRUE
$2,Mix Servo1 Sign = -1 ' -1 or 1 allowed. If Mixing for Elevon/V-tail is enabled, this is Elevon 1 servo direction
$3,Mix Servo2 Sign = 1 ' -1 or 1 allowed. If Mixing for Elevon/V-tail is enabled, this is Elevon 2 servo direction

$4,Servo 1 Gain = 9 ' 0 to 100 integer allowed, is 10x format. Aileron, or with elevons it is the aileron component of the mix
$5,Servo 2 Gain = 18 ' 0 to 100 integer allowed, is 10x format. Elevator, or with elevons it is the elevator component of the mix
$6,Servo 3 Gain = 12 ' 0 to 100 integer allowed, is 10x format. Throttle
$7,Servo 4 Gain = 0 ' 0 to 100 integer allowed, is 10x format. Rudder
$8,Servo 5 Gain = 10 ' 0 to 100 integer allowed, is 10x format. Pan servo, or Elevon3
$9,Servo 6 Gain = 10 ' 0 to 100 integer allowed, is 10x format. Tilt servo, or Elevon4
$10,Servo 7 Gain = 10 ' 0 to 100 integer allowed, is 10x format. Trigger Servo

$11,Servo 1 direction Sign = -1 ' -1 or 1 allowed. Aileron, or for Elevons it is the aileron component of the mix
$12,Servo 2 dirdction Sign = 1 ' -1 or 1 allowed. Elevator, or for Elevons it is the elevator component of the mix
$13,Servo 3 direction Sign = 1 ' -1 or 1 allowed. Throttle. 1 would be standard for electronic speed controls.
$14,Servo 4 direction Sign = 1 ' -1 or 1 allowed. Rudder
$15,Servo 5 direction Sign = 1 ' -1 or 1 allowed. Aux_1
$16,Servo 6 direction Sign = 1 ' -1 or 1 allowed. Aux_2
$17,Servo 7 direction Sign = 1 ' -1 or 1 allowed. Aux_3

$18,Servo 1 Upper Limit = 1688 ' Pulse width in microseconds, from 900 to 2100 allowed. Aileron, or Elevon1
$19,Servo 2 Upper Limit = 1667 ' Pulse width in microseconds, from 900 to 2100 allowed. Elevator, or Elevon2
$20,Servo 3 Upper Limit = 1900 ' Pulse width in microseconds, from 900 to 2100 allowed. Throttle
$21,Servo 4 Upper Limit = 2000 ' Pulse width in microseconds, from 900 to 2100 allowed. Rudder
$22,Servo 5 Upper Limit = 2000 ' Pulse width in microseconds, from 900 to 2100 allowed. Aux_1
$23,Servo 6 Upper Limit = 2000 ' Pulse width in microseconds, from 900 to 2100 allowed. Aux_2
$24,Servo 7 Upper Limit = 2000 ' Pulse width in microseconds, from 900 to 2100 allowed. Aux_3

$25,Servo 1 Lower Limit = 1350 ' Pulse width in microseconds, from 900 to 2100 allowed. Aileron, or Elevon1
$26,Servo 2 Lower Limit = 1371 ' Pulse width in microseconds, from 900 to 2100 allowed. Elevator, or Elevon2
$27,Servo 3 Lower Limit = 1100 ' Pulse width in microseconds, from 900 to 2100 allowed. Throttle
$28,Servo 4 Lower Limit = 1200 ' Pulse width in microseconds, from 900 to 2100 allowed. Rudder
$29,Servo 5 Lower Limit = 1000 ' Pulse width in microseconds, from 900 to 2100 allowed. Aux_1
$30,Servo 6 Lower Limit = 1000 ' Pulse width in microseconds, from 900 to 2100 allowed. Aux_2
$31,Servo 7 Lower Limit = 1000 ' Pulse width in microseconds, from 900 to 2100 allowed. Aux_3

$32, Path Angle Max = 30 ' 0 to 90 allowed (in degrees). "Cone" is shown in ASCII art below. Use 0 to disable TruTrak, but 30 is a good value
$33, Path Merge Line distance = 60 ' 5 to infinity allowed in meters. This is the half width of "highway" that we merge onto the line over. See ASCII Art below

$34,Roll Angle Limit = 30 ' Max allowed roll in degrees, from 5 to 40 allowed
$35,Pitch Angle Limit = 25 ' Max allowed pitch in degrees, from 5 to 40 allowed

$36,Steer Proportional Band Width = 195 ' Width (in degrees) to spread proportional control of roll response. 5 to 360 degrees allowed.
$37,Alt Proportional Band Width = 210 ' Altitude window (in meters) to spread proportional pitch response. 1 to infinity meters allowed.

$38,Steer_D = 35 ' Gain factor for "D" dampening term of heading control. 0 to 100 integer allowed. 10 is a good start
$39,Alt_D = 2 ' Gain factor for "D" dampening term of altitude control. 0 to 100 integer allowed. 10 is a good start

$40,MaxRate = 50 ' Max allowed pitch and roll rate of change in deg/second. 1 to 120,000 is allowed (0.01 to 1200 deg/sec)

$41,WP Distance Satisfy = 100 ' For departure WP sequencing, minimum distance (meters) to activate WP for departure. 10 to infinity meters is allowed.
$42,Hold radius = 200 ' Radius (in meters) of holding pattern at end of flight. 1 to infinity meters is allowed.
$43,Hold Direction = 0 ' 0 or 1 is allowed. 1 is CCW flight direction, 0 is CW rotation for end of flight hold pattern
$44,Hold Alt = 125 ' User-specified altitude for the default RTL hold pattern. 25 to infinity meters is allowed

$45,XY TPile Orientation = 0 ' Describes orientation of XY thermopile head. 0-7 are valid. See ASCII art in comments section.

$46,ThrottMid = 1400 ' 900 to 2100 allowed. Initial PWM value for Throttle, user-definable to control ESC arming or not upon boot up.

$47,log_freq = 0 ' Number of 1 second delay intervals between writes to LOG.txt. 0 to infinity is allowed. 0 is 5Hz.
$48,Num_Pulses = 20 ' Number of consecutive good pulses on Aux1 Rx channel required to switch flight mode. 1 to infinity allowed

$49,VoltScale = 51810 ' Conversion factor for analog voltage sensor. Units are number of mV per entire 3.3V analog scale. E.g. 51810 for Atto V1.7
$50,CurrentScale = 92623 ' Conversion factor for analog current sensor. Units are number of mA per entire 3.3V analog scale. E.g. 92623 for Atto V1.7

$51,Plane mass in grams = 0 ' Flying mass in grams
$52,Motor Efficiency Percentage = 80 ' Estimated efficiency percentage of electric motor + speed control. 80 is a good value for brushless outrunner, perhaps 40 for brushed motor.
$53,mAh usage upper limit abort = 0 ' 0 = don't use this function, 1 to infinity means YES and tells the used mAh RTL trigger

$54,Pitot Present = 1 ' 0 = lock throttle in non-RC, 1 = use pitot airspeed control, 2 = use GPS for speed with Cosine(Pitch) corrections
$55,Test Mode = 0 ' 0 = NO, 1 is YES. Causes AttoPilot to start Rx/Servo object, start 50Hz IMU object, and then hold. No GPS startup, no WP loading
$56,Ground Launch = 30 ' 0 = NO, 1 to infinity means YES and hold roll angle to zero until specified AGL altitude in meters is reached after launch in AutoMode

$57,Servo 1 D_Term = 16 ' 0 to 100 integer allowed, is 10x format. Aileron, or with elevons it is the aileron component of the mix
$58,Servo 2 D_Term = 12 ' 0 to 100 integer allowed, is 10x format. Elevator, or with elevons it is the elevator component of the mix
$59,Servo 3 D_Term = 0 ' 0 to 100 integer allowed, is 10x format. Throttle (not implemented)
$60,Servo 4 D_Term = 50 ' 0 to 100 integer allowed, is 10x format. Rudder
$61,Servo 5 D_Term = 0 ' 0 to 100 integer allowed, is 10x format. Aux_1 (not implemented)
$62,Servo 6 D_Term = 0 ' 0 to 100 integer allowed, is 10x format. Aux_2 (not implemented)
$63,Servo 7 D_Term = 0 ' 0 to 100 integer allowed, is 10x format. Aux_3 (not implemented)

$64,Hold Speed = 60 ' 5 to 255 integer allowed. Hold pattern airspeed target in km/h for when PitotPresent = 1
$65,Min Speed = 50 ' 5 to 255 integer allowed. Min allowed aispeed target for when PitotPresent = 1
$66,Max Speed = 140 ' 5 to 255 integer allowed. Max allowed aispeed target for when PitotPresent = 1

$67,Telem Baud = 38400 ' User can set this to ANY integer from 4800 to 230400. If unspecified, it defaults to 38400 baud

$68,MaxDistance = 10000 ' User-defined max distance (meters) from home to force abort and go to home. Default is 300km, but user can make less

$69,LoiterRadius(1) = 50 ' User-defined loiter radius, in meters. 0 to 32767 is allowed
$70,LoiterRadius(2) = 100 '
$71,LoiterRadius(3) = 150 ' To specify this at a waypoint, make last trigger digit (the 8th one from left)
$72,LoiterRadius(4) = 200 ' set to 1 through 9. To disable, set this trigger to zero (0)
$73,LoiterRadius(5) = 300 ' MUST be used in conjunction with non-zero 7th trigger value, otherwise loiter has LIMITED affect
$74,LoiterRadius(6) = 500 ' and the result would be plane will circle ONLY UNTIL it is line up with next waypoint.
$75,LoiterRadius(7) = 1000 ' T2 field sets the loiter direction. 0 (default) is clockwise, 1 is counter clockwise
$76,LoiterRadius(8) = 2000 '
$77,LoiterRadius(9) = 10000 '

$78,LoiterTime(1) = 10 ' User-defined loiter time, in seconds. 0 to 32767 is allowed
$79,LoiterTime(2) = 20 '
$80,LoiterTime(3) = 40 ' To specify this at a waypoint, make 2nd last trigger digit (the 7th one from left)
$81,LoiterTime(4) = 60 ' set to 1 through 9. To disable, set this trigger to zero (0)
$82,LoiterTime(5) = 120 ' MUST be used in conjunction with a non-zero 8th trigger value, otherwise time has no effect
$83,LoiterTime(6) = 240 '
$84,LoiterTime(7) = 600 '
$85,LoiterTime(8) = 1200 '
$86,LoiterTime(9) = 3600 '

$87,Trigger time interval (2) = 5 ' Specify value between parenthesis for Trigger field 3 (4th from right)
$88,Trigger time interval (3) = 10 ' 0 is no trigger for that waypoint
$89,Trigger time interval (4) = 20 ' 1 is trigger at waypoint only
$90,Trigger time interval (5) = 60 ' 2-5 are time interval triggers, in seconds
$91,Trigger Distance interval (6) = 100 ' 6-9 are ground distance interval triggers, in meters
$92,Trigger Distance interval (7) = 150 ' Time interval allowed from 0 to 32767 seconds
$93,Trigger Distance interval (8) = 200 ' Distance interval allowed from 0 to 32767 meters
$94,Trigger Distance interval (9) = 500 '

$95,Trigger Type = 1 ' 0 is logic controller from servo7 signal line, 1 is PWM servo controller from servo7
$96,Trigger Active = 1400 ' If trigger is logic, enter a 1 or 0 here. If PWM servo driver, enter servo position in microseconds
$97,Trigger Rest = 1600 ' If trigger is logic, enter a 0 or 1 here. If PWM servo driver, enter servo position in microseconds
$98,Trigger Duration = 5 ' Number of 0.2 second time intervals to hold trigger in active state for each episode of the trigger, 0 to 32767 allowed

$99, Roll Expo = 30 ' 0 is no Expo, otherwise 10X units amount to add per 90 degrees attitude.
$100,Pitch Expo = 30 ' 0 is no Expo, otherwise 10X units amount to add per 90 degrees attitude.

$101,AutoLock Distance = 0 ' exceed this and mode is forced into Auto. 0 means disable the feature.
$102,RTL mAh autoLock = 0 ' 0 is DISABLE, 1 is ENABLE. If mAh cutoff happens lock out other modes and go Auto for RTL
$103,PhotoDeadPre = 0 ' 0 to 50 allowed and is number of 0.2 sec intervals (0 to 10 seconds) pre trigger to lock attitude at level and idle throttle
$104,PhotoDeadPost = 0 ' 0 to 50 allowed and is number of 0.2 sec intervals (0 to 10 seconds) post trigger start to lock attitude at level and idle throttle
$105,StopNav = 0 ' 0 or 1 allowed. 0 is continue nav during motor off period of photo, 1 is stop nav and hold flat attitude during photo

$106,Pitot Offset = 21 ' -200 to 200 allowed. Value derived from indoor session of Test Mode (line 55 in this SET). Corrects hardware bias for accurate low airpseed range

$107, GPS Altitude = 0 ' 0 is NO, 1 is YES. Generally DO NOT enable this unless your UAV has hermetic sealed cabin. Pressure altitude is MUCH better

$108, Telem Freq = 1 ' Number of 1 second delays between telemetry updates out from Atto. 0 means maximum which is 5 Hertz

$109, Roll Bias = 0 ' 1X degrees. Put in non-zero value to seed the bias at start
$110, Pitch Bias = 4 ' 1X degrees. Put in non-zero value to seed the bias at start

$111, RC Dampen Roll = 14 ' 0 to 100 allowed though generally don't exceed the D_term in line 57
$112, RC Dampen Pitch = 10 ' 0 to 100 allowed though generally don't exceed the D_term in line 58
$113, RC Dampen Yaw = 35 ' 0 to 100 allowed though generally don't exceed the D_term in line 60

$114, Min_RollRate% = 25 ' 1 to 100 allowed. Is percentage of MaxRate to use when roll error is zero for soft landing on target
$115, Min_PitchRate% = 25 ' 1 to 100 allowed. Is percentage of MaxRate to use when pitch error is zero for soft landing on target

$116, Altitude by Throttle = 0 ' 0 is no 1 is yes. If yes, the next 6 lines need a value
$117, PitchSpeedGain = 60 ' Terminal velocity in km/h with motor off and pitch at -30. 0 to 1000 allowed
$118, ThrottAltGain = 18 ' 0 to 100 allowed. Throttle gain in special case of throttle altitude. Seperate from airspeed throttle gain.

$119, DistNear = 20 ' meters from altitude target. MUST be no larger than DistFar
$120, DistFar = 100 ' meters from altitude target. MUST be no smaller than DistNear
$121, NearB% = 50 ' % mixing Pitch Airspeed when at or closer to target alt than the DistNear value. MUST be no larger than MaxB
$122, FarB% = 80 ' % mixing Pitch Airspeed when at or farther to target alt than the DistFar value. MUST be no smaller than MinB

$######## END OF SETTINGS

The ArduCopter quad team is making tremendous progress--lightspeed stuff. Here is the latest render of one potential design, from Sandro Benigno.

Search for ArduCopter here for other work from this team. It's stunning...